NumberResearchThousands-blocks in 615-544
This prefix’s ten 1,000-number blocks and who holds each — 10 on record · from the daily NANPA thousands-block report, 09/20/2026
The ten 1,000-number thousand-blocks inside prefix 615-544 and who was initially assigned each. Under pooling these blocks often belong to different carriers — the single prefix-level “assignee” is usually just the pool / code holder, not who holds the numbers. ← all 615 blocks
Most active assignees, all time — NPA 615
New assignments by month
Sep 2026
Aug 2026
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Dec 2025
Nov 2025
Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2013-12-10 | 615-544-0XXX | 0000–0999 | Assigned | ONVOY, LLC - TN | 525E | FAIRVIEW | TN |
| 2008-05-06 | 615-544-1XXX | 1000–1999 | Assigned | LEVEL 3 COMMUNICATIONS, LLC - TN | 4806 | FAIRVIEW | TN |
| 2025-09-10 | 615-544-2XXX | 2000–2999 | Assigned | TERRA NOVA TELECOM INC. | 145J | FAIRVIEW | TN |
| 2020-10-01 | 615-544-3XXX | 3000–3999 | Assigned | ONVOY, LLC - TN | 525E | FAIRVIEW | TN |
| 2020-09-04 | 615-544-4XXX | 4000–4999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | FAIRVIEW | TN |
| 2010-02-02 | 615-544-5XXX | 5000–5999 | Assigned | BANDWIDTH.COM CLEC, LLC - TN | 124F | FAIRVIEW | TN |
| 2020-05-19 | 615-544-6XXX | 6000–6999 | Assigned | ONVOY, LLC - TN | 525E | FAIRVIEW | TN |
| 2012-04-04 | 615-544-7XXX | 7000–7999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - TN | 7977 | FAIRVIEW | TN |
| 2014-02-20 | 615-544-8XXX | 8000–8999 | Assigned | CENTURYLINK COMMUNICATIONS, LLC | 508J | FAIRVIEW | TN |
| 2023-05-15 | 615-544-9XXX | 9000–9999 | Assigned | ONVOY SPECTRUM, LLC | 624H | FAIRVIEW | TN |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.